Merging functional electronics with 3D printing that adds layers of a hydrogel matrix allows researchers to grow cartilage tissue and form a simple bionic ear. Now they just need to add blood vessels and skin.

Using 3-D printing tools, scientists at Princeton University have created a functional ear that can “hear” radio frequencies far beyond the range of normal human capability.

The researchers’ primary purpose was to explore an efficient and versatile method of merging electronics with tissue. The scientists used 3-D printing of cells and nanoparticles — with an off-the-shelf printer purchased off the Internet — followed by cell culture to combine a small coil antenna with cartilage, creating what they term a bionic ear.